This invention relates to pesticides for agricultural, horticultural including aquaculture and particularly to products that directly kill or impact the life cycle of simple celled organisms such as microscopic insect larvae, algae, fungi, bacteria, mosses, and bryophytes such as liverworts. Pesticides, also known as biocides, are used to control these pests. The pests are commonly found in commercial and agricultural greenhouse, landscapes, nursery fields, storage areas, and aquaculture sites. The invention has applications in all aspects of horticulture and agriculture. Formulation variations can be applied directly to all types of plant, flower and turf tissue without any danger of phytotoxicity when used in accordance with prescribed directions.
Pesticides are an important component of agricultural production throughout the world. Pest control pertains to a wide range of environmental interventions that have their objective to kill or reduce to acceptable levels moss and algae pests, plant pathogens and weed populations. Specific control techniques include chemical, physical and biological control mechanisms. It has been estimated that pests annually destroy about 35% of all food crops before they are harvested and another 10-20% after the food is harvested.
Chemical controls include chemical agent pesticides that include herbicides, for the control of weeds, moss and algaecides for the control of moss and algae pests and fungicides for the control of soil and plant pathogens that include bacteria, fungi and viruses. Herbicides that destroy or inhibit plant growth account for over half of the pesticides that are uses world wide, with 30-35% of pesticide production in the form of moss and algaecides and the balance and the form of fungicides.
All living organisms are composed of cells. The result of biosynthesis is cell growth. Microorganisms live in natural habitats in which their growth is affected by interactions with populations of other microbes, as well as by the physical and chemical characteristics of their environment. Some microbial species can have devastating effects on human beings by causing infectious diseases. A great success of the science of microbiology has been the control of fatal infectious diseases in developed countries. However, these diseases are still important causes of death in less developed parts of the world. Microbes are also important in agriculture and food spoilage.
The growth of bacteria such as E. coli depends upon not only the provision of nutrients, but also the existence of appropriate environmental conditions such as temperature, pH, water activity, and aeration. Species differ in the range of these factors within which they will grow.
In general, organisms can grow over a temperature range of 30 to 40 C. However, species differ in range, and four categories have been delineated on this basis. Mesophiles have optimal growth temperatures in the range 20-50 degrees C.; that is, the temperatures most common on the earth's surface or in animals. Psychrophiles have optimal temperatures below 15 C. These organisms are killed by exposure to room temperature. They function at low temperature by having high contents of unsaturated fatty acids in their membranes. These molecules remain fluid at temperatures where membranes containing saturated fatty acids are nonfunctional.
Psychrotrophs can cause spoilage of refrigerated products, such as food or blood. They grow fastest at temperatures above 20 C, and therefore are likely to contaminate these products, but are capable of slow growth at refrigerator temperatures.
Most microbes grow somewhere within the pH range of 5 to 9; most natural environments fall within this range. However, species do exist which grow at pH extremes. Fungi tend to grow at lower pH values than do bacteria.
It is important to control populations of simple celled organisms that affect ornamental and agricultural crops due to the ability of the organisms to inflict major damage to the crops that directly and indirectly cause crop loss. Moss and algae can directly affect crop loss due to the ability of both algae and moss to grow quickly over soil surfaces and prevent the plant from growing. In addition moss and algae also directly affect the aesthetics of the plant, which in the case of ornamental crops such as cut flowers and house plants make the crop unmarketable.
Moss and algae pose indirect problems to the production of plants due to their developing a parasitic relationship with the plant material. Both algae and moss tend to grow on the soil surface thereby denying the plant of nutrients and creating a sometimes-impermeable cap that prevents the plant's root system from getting water.
Most modern day moss control products (mosscides) and algaecides are comprised of long lasting, synthetic compounds that affect the cell structure of simple celled organisms on contact. While these pesticides have proven to be very effective at controlling moss and algae they have also contributed to an unacceptable environmental cycle that directly affects human health and welfare as well as direct and indirect environmental damage. Modern day moss and algaecides primarily work by placing a poison or toxin residue on the surface of plant tissue or by directly spraying the moss and algae pest with the poison compound.
There are several problems that arise from using chemical moss and algaecides and they are as follows:
Resistance: Since traditional moss controls and algaecides work on the principal of chemical toxicity, the moss and algae is capable through genetic mutation of developing a resistance to the toxins that affect it. In the moss and algae world, where generations are produced in the pans of weeks, the problem of genetic resistance is common. Within a very short amount of time, many mosses and algae that were formally susceptible to certain chemical compounds, find that sometimes within the span of a few years, the chemical either does not produce a kill or the dosage must be increased to produce a kill.
This is why moss and algaecide applicators must cycle their applications of different chemical compounds so as not to allow moss and algae they are trying to control to become accustom to any one chemical compound and ultimately to become immune to the chemical. This practice of chemical rotation is both times consuming and expensive, since the applicators must have at minimum three different chemical compounds for various types of moss and algae pests.
Human Toxicity: Most chemical moss controls and algaecides must be used and applied with extreme caution. The applicator must at all times wear special protective personal protection clothing. This includes the use of respirator and eye protection, as well as chemical impervious coveralls and gloves. Since the moss and algaecides produce a toxic residue and are by nature long lasting and complex compounds, over a period of time, direct exposure to moss and algaecides can lead to human health concerns and in some cases direct exposure to certain moss and algaecides can lead to toxic shock and death.
Environmental Damage: Due to the very nature of the moss controls and algaecide that is designed to leave behind a toxic residue on either plant surfaces or in the soil, environmental damage is a direct concern. With the increasing concern over the impact of groundwater by complex pesticide compounds that do not break down into innocuous substances. It has been documented that pesticide compounds have directly impacted groundwater aquifers across the country and become a direct threat to environmental security.
In addition to concerns about groundwater impacts, treatments for moss, algae and other simple cell microorganisms have the capacity to impact non-target organisms within the environment that come into contact with the chemical compounds. These organisms include fish, birds, other non-pest moss and algae, and all forms of animal life. The impact of the insecticide DDT and other chemical treatments ostensibly intended to benefit society while in fact entering the food chain and impacting birds such as the American bald eagle, storks, rainbow trout and others has been well-documented.